1.11 About Geodetic Datum

The Kashmir supports different Geodetic datum.
There are two different definitions for datum: one for map and another for display.
The map datum is a base of the map, which is defined exclusively for the map. Another map datum is valid for utilization of the map. For Japanese map TOKYO datum is normally used. The GSI Japan decided to use the same datum as WGS84 form 2000. This causes shift of coordinate, which you could know in advance by selecting WGS84 as displaying datum.

Since the elevation data content no information on the geodetic datum it is defined in following way  as default.

Map Default Geodetic Datum
Mesh File TOKYO
Digital Map 250m Grid TOKYO
Digital Map 50m Grid TOKYO
Bitmap TOKYO
Grayscale TOKYO
USGS 30 sec grid (GTOP30) WGS-84
USGS 3sec grid (GTOP3) WGS-84
CHsystem Map TOKYO
EVM Map TOKYO or WGS-84 (depending on the place)
DCM Map TOKYO or WGS-84 (depending on the place)

For changing the geodetic datum select [View] - [Select Datum].

If you change the geodetic datum the place name, GPS tracking, routing, and way points are adjusted according to the new datum automatically.
Changing the geodetic datum causes no displacement of the linked icons.

For normal use select TOKYO for Japan and WGS-84 for other places.

Meaning of Datum for each data

Data of place name, Link icon, waypoint, route, and track can have an independent datum.
The datum shows which datum has been used for the coordination of the map. Changing the datum causes  no coordination change, which causes shift on the map.

To convert the coordinate without shift, execute [Datum Conversion] by the property of each data. This converts the coordinate value without shift.

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